Covering assembly for crucible used for evaporation of raw materials
US7291224B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 2, 2005 |
| Grant date | Nov 6, 2007 |
| Priority date | — |
| Expiry date | Sep 19, 2025 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC23C14/0694
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
The present invention provides an assembly comprising two plates or covers, one of which being an outermost plate or cover, and both, at least in part having a perforation pattern over a surface area covering an open side of a crucible having a bottom and surrounding side walls containing raw materials, wherein said outermost cover is mounted at a distance farther from the said crucible than said cover covering said open side of a crucible, and wherein both covers are mounted versus each other, so that, when viewed through an axis in a direction perpendicular to the bottom of the crucible from a distance to said outermost cover of at least 10 times the distance between said two plates or covers, its contents cannot be observed as their perforations and the crucible are never forming one line, perpendicular to the plane formed by said bottom.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.